Archive for 2011

First, we’ve added a section for ROBOTC’s new Natural Language Library. You’ll find tons of print materials, ranging from guides describing each Natural Language command available for the VEX PIC and Cortex to dedicated helper guides for each of the VEX Sensors. You can find the new page in the VEX Cortex Video Trainer by going to the Fundamentals section and choosing Natural Language.

Second, there are 4 new tutorial videos that show how to use the Ultrasonic Rangefinder, complete with helper guides and programming challenges. You can find them by going to Sensing and choosing Forward until Near.

The VEX Cortex Video Trainer is available for free, online. To purchase a copy that you can install on each computer in your classroom, visit the RoboMatter store.

Support on Prolific cables for workaround to protocol errors for IFI defined special Cortex messages. Previously was only implemented on integrated USB-to-Serial.

Correct incorrect code generation for a parameter “call by reference” variable which is itself a “call by reference” variable.

Add new intrinsics for VEX LCD to specify line and char position of the “Put”. Add alias “setLCDPos” for “displayLCDPos”

Bump version to 9.04 / 3.04. Rebuild firmware.

Eliminate NXT EXE encrypted file headers. It causes a bug with >160 subroutines on NXT. Need to rebuild NXT firmware to support this change.

When return statement from a “non void” function is unreachable because function contains an infinite loop compiler used to generate an error message that “No return statement from non-void function”. Now it generates a warning that an infinite loop prevents return.

LEGO George the Giant Robot!

He is controlled via a PlayStation 2 controller, he can move about, rotate his upper body, move his arms / shoulders and grab on to items. His head also rotates, moves up and down and if you get too close, his eyes will rotate.

Video of LEGO George:

I asked burf2000 some questions about his robot:

What inspired you to build this robot?

“I have always loved robotics and so Lego for me was a medium to build it in, I built another large robot last year but was not so successful. That one was based off T1 from Terminator 3. I wanted to keep things simple on this one due to size. It weights around 20KG. I also loved the Short-circuit films (johnny 5).”

How long did it take to make?

“This one took around 3 months of the odd evenings and days, We just had a baby (my wife) so getting time has been quite hard. However my wife is very supportive and knew I needed to build this for a show. (http://www.greatwesternlegoshow.com/).”

What are your future plans with the robot?

“Glad you asked this, currently I am improving certain parts of this which I am not happy with like shoulder joints, main bearing and turning. Once they are done, I am going to build a second robot to keep him company. Its going to be another large one, using more NXT’s and hopefully will go round on his own. My aim is to get a whole display of large robots moving around and interacting with each other.”

I thank you, burf2000, for submitting LEGO George. We can’t wait to see his successor!

We found a great video that a user made on Youtube (username: JosGJosG) that talks about Third Party Sensors.

JosGJosG takes you through starting up ROBOTC and going through the Preference settings in order to enable the ability to use Third Party sensors.

Description of the video (from youtube):

When ROBOTC is downloaded, it is initially set up to recognise only LEGO sensors. A set-up change has to be made to allow ROBOTC to recognise third party sensors, (HiTechnic, MindSensors, Firgelli, etc.). This video shows how to make that change, and also briefly mentions the difference in set-up between the full ROBOTC, and the simplified Natural Language ROBOTC. This video is one of a series of free video tutorials that introduce students to LEGO MindStorms NXT-G and to the use of Third Party Sensors; you can see them at www.DrGraeme.net.
Enjoy!

We’ve just released ROBOTC 3.03. Head on over to the download pages to download the latest version!

3.02 to 3.03 Change log:

Fixed issue with nMotorEncoderTarget when issuing a positive target with a negative speed.

Removed windows that would cause Virtual Worlds to crash when opening.

Fixed problem with large files not compiling to robot controllers. The Maximum size of user program was incorrectly given as 16K. Changed to 128K. Also added error messages to prevent “silent” failure.

Encoders provide a great way for you to control where your robot goes. The video that is posted below is for someone who has never used encoders.

In this video we will talk about what encoders are used for and open a sample program that allows a user to see how the code works. New programmers can try this program out using the Robot Virtual World software found at: www.robotc.net/rvw

The ROBOTC team modified both the FTC Bowled Over and VEX Gateway Challenge Virtual Worlds to include four different starting positions and improved physics. Each robot challenge has four different starting positions. The new options in the virtual worlds are designed to allow the team’s programmers to begin their path planning for the autonomous portion of the challenge while the rest of the team completes the robot. Teams will be able to begin to build robot behaviors like straight for a number of encoder counts, turning a specific angle, linetracking, forward until sonar or touch sensor before their actual robot is complete.

You can see a simple example of the FTC Bowled Over Robot Virtual World here:

This is my power functions robot named Grumpy.
Like other robots he has some basic functions like:

Driving back-/forward

Turning

Lower and raise his arms

Open and close his claw to pick things up

But that wasn’t enough for me. I wanted him to have some personality. To do that I added some head movements. He can shake his head left/right and move his neck back- and forward. While driving he always looks in the direction he’s going. He can also move his eyebrows up and down.